| Message ID | 20140829091439.152D51ABD63@localhost.localdomain (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Scott Wood |
| Headers | show |
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index 5037420..4a49ff3 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -638,9 +638,11 @@ modified_instr: /* special handling for r10,r11 since these are modified already */ 153: mfspr r11, SPRN_SPRG_SCRATCH1 /* load r11 from SPRN_SPRG_SCRATCH1 */ - b 155f + add r10, r10, r11 /* add it */ + mfctr r11 /* restore r11 */ + b 151b 154: mfspr r11, SPRN_SPRG_SCRATCH0 /* load r10 from SPRN_SPRG_SCRATCH0 */ -155: add r10, r10, r11 /* add it */ + add r10, r10, r11 /* add it */ mfctr r11 /* restore r11 */ b 151b #endif
Branching takes two cycles on MPC8xx. Lets duplicate the two instructions and avoid the branching. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> --- arch/powerpc/kernel/head_8xx.S | 6 ++++-- 1 files changed, 4 insertions(+), 2 deletions(-)